1. Field of the Invention
The present invention relates to an electrical connection, of one or more conductive coils to a metal terminal pin extending rearwardly from a tip electrode in an electrode assembly at the distal end of a pacing lead which is used to apply electrical pulses to the muscles of a heart.
2. Description of the Prior Art
Heretofore various electrical connections including a wound conductor on a bar or pin in an electrical connection have been proposed. Examples of such previously proposed electrical connections are disclosed in the following U.S. patents:
______________________________________ U.S. PAT. NO. PATENTEE ______________________________________ 1,584,533 Hands 1,779,804 Dubilier 2,104,888 Sparh 2,759,166 Mallina 2,792,560 Bollmeier 3,243,755 Johnston 3,649,743 O'Loughlin ______________________________________
The Hands U.S. Pat. No. 1,584,533 discloses a terminal connection for attaching resistor heating elements to a furnace terminal. This terminal connection is formed by a helically wound portion at the end of a heating wire which portion is received about a threaded shaft of a bolt. A nut is then received over the helically wound portion on the bolt shaft.
The Dubilier U.S. Pat. No. 1,779,804 discloses a lamp socket including a coiled spring which receives the neck of a lamp.
The Sparh U.S. Pat. No. 2,104,888 discloses a device for connecting a flashlight bulb to a battery and includes a wire into one coiled end of which a flashlight bulb is screwed.
The Mallina U.S. Pat. No. 2,792,560 discloses a wire connector for mechanically fastening the ends of solid or stranded electrical wires to rivets, bolts other rods or wires, etc. The connector includes a center core portion or tube through which a solid or stranded electrical wire is inserted to place same on a serrated surface and held thereon by means of a steel spring threaded thereover.
The Johnston U.S. Pat. No. 3,243,755 discloses an electrical connector utilizing a pair of conical springs of similar size and arrangement, wherein one of the springs acts as a male member and the other as a female member and upon mating of the pair, connection is effected by contact of turns of the springs.
The O'Loughlin U.S. Pat. No. 3,649,743 discloses a wrapped wire connection comprising an elongate post having turns of a wire coductor Wrapped therearound with a deformable sleeve received over the wire turns.
In the present connection of an electrode assembly at the distal end of a pacing lead three components are needed. One is the bared coiled end of the single or multiple wire (filar) conductor of the lead. Another is a terminal pin or shank extending rearwardly from a mushroom shaped tip of a tip electrode. The third component is a sleeve or collar received over the bared coiled end on the pin or shank. The sleeve or collar is staked or crimped to secure the coil to the pin or shank.
As will be described in greater detail hereinafter, the electrical connection of the present invention differs from the wire connections disclosed in the patents referred to above and from the present staking of a sleeve received over a coil on a pin in an electrode assembly of a pacing lead by providing for the attachment of a coiled bare end of a single filar conductor or a multifilar conductor at the distal or proximal end of a pacing lead onto a terminal pin extending rearwardly from a distal tip electrode or forwardly from a proximal terminal electrode primarily by threading of the filar(s) onto a spiral or thread formation on the pin of the distal or proximal electrode.